Synthesis of 2-oxindoles via 'transition-metal-free' intramolecular dehydrogenative coupling (IDC) of sp2 C–H and sp3 C–H bonds
نویسندگان
چکیده
The synthesis of a variety of 2-oxindoles bearing an all-carbon quaternary center at the pseudo benzylic position has been achieved via a 'transition-metal-free' intramolecular dehydrogenative coupling (IDC). The construction of 2-oxindole moieties was carried out through formation of carbon-carbon bonds using KOt-Bu-catalyzed one pot C-alkylation of β-N-arylamido esters with alkyl halides followed by a dehydrogenative coupling. Experimental evidences indicated toward a radical-mediated path for this reaction.
منابع مشابه
Transition metal-free intramolecular regioselective couplings of aliphatic and aromatic C-H bonds
Cross-dehydrogenative couplings of two different C-H bonds have emerged as an attractive goal in organic synthesis. However, achieving regioselective C-H activation is a great challenge because C-H bonds are ubiquitous in organic compounds. Actually, the regioselective couplings promoted by enzymes are a common occurrence in nature. Herein, we have developed simple, efficient and general transi...
متن کاملCopper-catalyzed oxidative C(sp3)–H/C(sp2)–H cross-coupling en route to carbocyclic rings† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc00250e Click here for additional data file.
The selective construction of C–C bonds, the essential link in organic molecules, in more efficient ways is always the central topic in synthetic chemistry. In the past several decades, transition-metal-catalyzed C–C bond construction via the activation of ubiquitous C–H bonds has attracted increasing attention, due to the atom and step economy. While the recent fast developments in this area o...
متن کاملThe intramolecular sp2 and sp3 C-H bond activation of (p-cymene)ruthenium(II) N-heterocyclic carbene complexes.
The intramolecular sp2 and sp3 C-H activated products, as well as the monometalated products, based on the "(p-cymene)Ru(NHC)" framework were synthesised by treatment of a series of NHCs (1-R-3-methylimidazol-2-ylidene [R=Ph (1), Bn (2), t-Bu (3), i-Pr (4), Mes (5), Cy (6)] and 1,3-bis(isopropyl)imidazol-2-ylidene (7)) with [(p-cymene)RuCl2]2 under mild conditions. A new NHC precursor (1-tert-b...
متن کاملMetal free TBHP-promoted intramolecular carbonylation of arenes via radical cross-dehydrogenative coupling: synthesis of indenoquinolinones, 4-azafluorenones and fluorenones.
A metal-free, TBHP-promoted economical route is developed via the sp(2) C-H bond functionalization strategy for the synthesis of indenoquinolinones, 4-azafluorenones and fluorenones. Reactions provided excellent yield of the products under mild conditions. We have successfully synthesized 11H-indeno[1,2-b]quinolin-11-one, an antibacterial agent, in excellent yields.
متن کاملIron-catalysed tandem cross-dehydrogenative coupling (CDC) of terminal allylic C(sp3) to C(sp2) of styrene and benzoannulation in the synthesis of polysubstituted naphthalenes.
A novel iron-catalysed tandem cross-dehydrogenative coupling and benzoannulation process was developed for the synthesis of biologically and synthetically important polysubstituted naphthalene derivatives from simple 1,2-aryl-propenes and styrenes in moderate to good yields.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 12 شماره
صفحات -
تاریخ انتشار 2016